An item of clothing normally worn out of doors as the outermost layer of clothing.(noun)
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Use "outer garment" in a sentence
"The inner lining, similar to a child’s snowsuit, was relatively comfortable compared to the tight rubber outer garment that resembled a frogman’s suit."
"chlamys The cloaklike outer garment worn by Greek men."
"Dominicans, etc.) retain for the mozzetta the colour of the outer garment of the habit of the respective order."